mono/MonoGame — pull request #1469 by nkast (2013-02-27 13:55:33+00:00)
Title: GetShaderResourceView throws exception when called from TextureCollectio...

...n.SetTextures

Some effects like DualTextureEffect and EnvironmentMapEffect use two
textures.
Once used, the second texture stays at GraphicsDevice.Textures[1]
forever.

In case you later dispose the said texture, a NullReferenceException is
thrown.